Thanks everyone for the advice
First, I did check Google, didn't really find anything to stop bootup at the bios screen (from there I can choose my drive)
Yes, I have been pressing the delete key to open the Bios then go to the boot menu.
That is a Pain. Every single time I boot. That's why I wanted my new computer to behave like my old computer.
The old one boots up and stops at the bios screen where I can select my drive.
I don't have multiple OS on multiple partitions of a drive. Each install has it's own Windows To Go drive install all to itself.
These SSD portable drives (mainly SanDisk with the keyhole) all show in the Bios screen. All I need is to know how to set the computer to stop on the Bios Screen while booting up (without pressing any keys).
I use these portable Sandisk SSD on both of my computers. When on the Oldie, bootup stops at the bios screen every time it boots, if I am at the computer or not (sometimes if I get a phone call when I finish and come back to the computer it is still waiting for me to select the drive.
When on my new computer, the same drives do not stop at the Bios Screen on its own. I have to hit the delete key. Every time.
It has been awhile since I made one of the Windows to Go (Hasleo) so I'm not sure if I used Legacy or Uefi. I think it might be legacy as that is what Hasleo suggests for maximum compatibility. They Windows install itself does work on both my Old and New Computer. Whether the Oldie stops at the Bios Screen, or I keep hitting the delete key on the New.
If a Boot Loader or manager will work for what I want, I am open to that. Way way back in the day I tried a dual boot setting and got rid of it fast. So not sure how this will work when I plug and unplug various SSD portable Sandisk drives.
My Oldie has 3 and 4 portable SSD USB drives usually pluged in in all the time. When it stops at the Bios I just select one and it continues to boot. Sometimes I plug and unplug drives to check some files out, and everything still works as it should.